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The Preview window displays a smaller version of the rendered image. This window shows the progress of the render and the adjustments interactively, and the changes are only transferred to the big window on each integer Sampling Level value that is reached (if the render is running), of or when you hit the Refresh button (if the render is stopped).
Preview window
Refresh buttons
In the render area you’ll find this group of buttons:
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Refresh button: starts refreshing the render and/or denoiser images with the latest changes.
R: when active, the refresh button will refresh the render pass.
D: when active, the refresh button will refresh the denoiser channel.
This group of buttons can be relocated to the four corners of the render area. There’s a dropdown menu in the Preferences window > Appearance section for that:
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Also, you can use these shortcuts:
Ctrl + Alt + NumKey 4: bottom-left
Ctrl + Alt + NumKey 5: bottom-right
Ctrl + Alt + NumKey 7: top-left
Ctrl + Alt + NumKey 8: top-right
Fast Multilight Preview
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